LABORATORY AND DIAGNOSTIC TESTS.
11TH EDITION
• AUTHOR(S)FRANCES FISCHBACH;
MARGARET FISCHBACH; KATE STOUT
TEST BANK
Ch. 1 — Diagnostic Testing
Stem (2–4 sentences): A nurse prepares a patient for a
scheduled blood draw for multiple chemistry tests. The patient
reports eating breakfast two hours earlier despite instructions
to fast for 8–12 hours. Which action best reflects appropriate
pretest nursing responsibility?
A. Proceed with the blood draw and note “nonfasting” on the
requisition.
B. Cancel the test and ask the patient to come back after an 8–
12 hour fast.
C. Draw the blood and phone the provider immediately for new
orders.
,D. Substitute a capillary (fingerstick) specimen since it’s faster
and avoids fasting.
Correct answer: B
Rationales
• Correct (B): The textbook emphasizes that fasting is
required for many chemistry panels to avoid inaccurate
results due to recent food intake; rescheduling preserves
test validity and prevents misleading interpretation.
Nursing responsibility includes confirming and enforcing
preparatory instructions.
• Incorrect (A): Documenting “nonfasting” may be
acceptable in some contexts, but the best action when
fasting is required is to reschedule to obtain valid baseline
results.
• Incorrect (C): Calling the provider for orders without first
addressing the pretest preparation is inefficient; the
provider may choose to reschedule once informed, but the
nurse’s priority is to prevent an invalid specimen.
• Incorrect (D): A capillary specimen does not correct the
physiologic effects of a recent meal on many chemistry
analytes and may provide noncomparable results.
Teaching point: Verify and enforce fasting instructions;
reschedule when preparatory steps weren’t followed.
,Citation (Simplified APA): Fischbach, F., Fischbach, M., & Stout,
K. (2021). A Manual of Laboratory and Diagnostic Tests (11th
ed.). Ch. 1.
Ch. 1 — Diagnostic Testing
Stem: A patient in the ED is septic and the provider orders
blood cultures and broad-spectrum antibiotics. Blood cultures
are scheduled immediately. What is the nurse’s best timing
action regarding cultures and antibiotics?
A. Draw blood cultures after giving the first antibiotic dose to
ensure safety.
B. Draw blood cultures before starting antibiotics to maximize
yield.
C. Start antibiotics immediately; blood cultures are optional if
sepsis is suspected.
D. Delay both cultures and antibiotics until lab personnel are
available.
Correct answer: B
Rationales
• Correct (B): Chapter 1 stresses timing: microbiologic
specimens such as blood cultures should be collected
before antimicrobial therapy when possible to increase
diagnostic yield. In suspected sepsis, cultures before
antibiotics are preferred.
, • Incorrect (A): Giving antibiotics first reduces culture
sensitivity and may result in false-negative cultures.
• Incorrect (C): Blood cultures are not optional in sepsis
workup; they guide targeted therapy.
• Incorrect (D): Delaying antibiotics in true sepsis is
dangerous; however, cultures should be obtained promptly
before administration when feasible.
Teaching point: Obtain microbiologic cultures prior to
antibiotics whenever possible.
Citation (Simplified APA): Fischbach, F., Fischbach, M., & Stout,
K. (2021). A Manual of Laboratory and Diagnostic Tests (11th
ed.). Ch. 1.
Ch. 1 — Diagnostic Testing
Stem: A nurse receives a point-of-care (POC) blood glucose of
42 mg/dL in a postoperative patient who is drowsy. According
to diagnostic-testing priorities, what is the nurse’s best
immediate action?
A. Recheck with a laboratory serum glucose in 30 minutes to
confirm.
B. Give an immediate source of fast-acting carbohydrate (or IV
dextrose if NPO).
C. Document the low value and wait for the provider to round.
D. Ignore the POC value because capillary values are unreliable.